Interesting SVG filter effects are produced when you combine multiple filter primitives inside a single filter. Even more interesting is when you can output the results of different primitives as layers that can be displayed together.

There will be times when the effect you want to add requires an additional image beyond the source graphic. Fortunately SVG provides a way to allow us to load external images inside a filter and make them part of the effect.

SVG filter primitives are the building blocks to create the effect you desire. You can use multiple primitives inside a single filter for more interesting effects, however, you need to make the different primitives aware of each other.

SVG filter effects apply graphic operations to images and elements in nondestructive ways. You can add filters to any SVG element or text and even to bitmapped images. Because SVG filters are nondestructive the original image is never changed and you can return to it by removing any filters you’ve added.